Improvement in voltaic piles



'UNIATED STATE-s ALFREDC.l GARRATT, 0F BOSTON, MASSACHUSETTS.

IMPROVEMENT IN VOLTIC PILES.

Specification forming part of Letters Patent No. 72,628, datediDecember'24, 1867;

To all 'whom it may concern vBe it known that I, ALFRED C. GARRATT, M. D., of Boston, in the county of Suffolk and State of Massachusetts, have inventedpan Improved Voltaic Pile or Battery; and do hereby declare the samelto be'fully described in the -following specification and represented inthe accompanying drawings, of which- Figure l is a side elevation, Figs. 2 and 3 longitudinal sections, and Fig. 4 a transverse section, of it.

The ordinary arrangement ofmetals and cloth constituting the voltaic pile-viz., first, a disk or plate of copper; second, a plate of zinc on the copper; and, third, a piece of wet cloth on the'zinc, these being followed by another series of copper, zinc, and cloth, and so on to any number-is very well known. It is also known that this arrangement, first made by Volta, acts irregularly, and only for'a short time at best, and cannot be excited to action again without taking all the plates and cloths apart, cleansing the metals, wetting the cloths, and relaying the whole together again. For these reasons the voltaic pile has generally fallen into disuse. Still the primary current of electricity obtained from a portable dry or moist pile is exceedingly desirable in medical practice, as also for experimental and other useful purposes, since the secondary or induced current cannot replace it in very many cases. Besides, this kind of pile is not only portable, but it is free from vitriol or caustic acids.

The object of my invention or improvement is to provide a portable and durable primary battery of power, one not expensive, free from destroying acids, and always ready foruse Without material labor or delay.

I disclaim the order and series of disks or plates of metals and cloths as arranged in the common voltaic pile, the nature'of my invention consisting in a new and useful arrangement and connection of cast bars of zinc and yellow metal or copper, and Woolen, cotton, or other porous cloth in strips, all as represented, and adjusted in an insulating-frame of hard rubber or wood boiled in oil, or wood covered with varnish. Metal for the frame may he used to very good advantage if lined with gutta-percha, rubber, or other insulating material, it being stronger and less bulky. In

fact, my battery isv composed, first, of cast' zinc bars, such being squarev o`r rectangular in rectangular in transverse Section5' third, of

sure metallic connections of thesebars by soll der or Welding at theirends', apspacev being left betweenl every couple so united, in orderA that air and' moisture may pass betweenv them; fourth, the laying up or arranging these bars in pairs, each of which is composed of the two metals, having a space between them, tapelike cloths being arranged between the pairs, and the whole being placed in an insulatingframe r4of hard rubber, Wood, or metal, so as to be secure and yet convenient to be moistened with vinegar or water at any desirable moment for exciting galvanic action, or for being cleansed by soaking in Water or Warm saleratus-water and rinsing.

In the structure of this battery-pile each bar b or z of it has a cloth, c, or some kind of porous substance, on one side`of it-that is, between a brass bar, b, and a zinc bar, z. It also has a space, s, on the other side of itthat is, between the brass and the zinc hars-so that air and moisture may pass between them. This arrrangement I consider new and very important, because it increases the power of the elements.

In the drawings I have represented each of the brass bars by the letter b, and each ofthe zinc bars by the letter z. Each of the strips of cloth is indicated by the letter c. The frame f for holding them consists of two wooden grooved bars, 'w w, arranged parallel to each other, and connected at their extremities by metallic cross-ties or bars t t.

I purpose, inthe manufacture of the perpet' ual piles, to leave out one metal at each end of the pile, so as to make the direction of the current the same as that from the galvanic battery-viz., the copper pole positive, and the zincl pole negative, because in the original voltaic pile these poles are always reversed to the galvanic.

I have discovered that bars of cast metal, without being rolled or hammered on their surfaces, so as to condense the particles com posing such surfaces, are far preferable to rolled or hammered bars, and cause the battery or pile, when made from them, to be very much more powerful.

In connecting a bar of one metal to one of another--as, for instance, a bar of zinc to a bar of brass-I arrange them parallel, with a narrow space between them, and with small tacks between them, such being as shown in Fig. 5, which isa longitudinal section of two of the bars, b z, connected Vby solder s s at their ends, and having small copper nails or tacks 'n n disposed between them, the space being shown at m. Inthis way I form and connect each pair of the bars composing the pile. To excite the battery it will only be necessary to brush over one side of it with vinegar or other acidulous liquor proper therefor. rlhesoldering at the ends of every two bars of zinc and brass, with a space, m, between the bars, is not only to make sure'4 metallic contacts, (and have a perpetual pile,) but also, by means of the space between the bars, to greatly increase the strength ofthe given elements and the length of time of their action.

Holes may be made in the terminal bars (as also in every fifth or tenth bar of the series) for receiving the wire ends of the electric con' ductors, in order to lead off the whole current of the series, or anyndesired portion of it, for the work to be accomplished.

I claim as my invention- 1. The improved voltaic pile or battery composed of the two different metals in the form of bars, arranged with a strip of cloth between each two pairs of them, and with a space between the bars of each pair, such bars being connected at their' ends, as set forth, and` the whole being held in place by a frame, substantially as described.

2. In a battery of such kind, the arrangement and combination of metallic pins or tacks n and solder s with the two zinc and brass or copper bars b z, the whole being as specified.

ALFRED o. GARRATT.

Witnesses R. H. EDDY, F. P. HALE, Jr. 

